I'm looking for:
A VCO chip where all the VCO components are on-chip, in other words I feed
it some control voltage and it produces an output frequency. I don't want
any external components like R/L/Cs or crystals that might have harmonics
of
the output frequency on them.
Broadband: something like 0-1000MHz, where '0' and '1000' are fairly
flexible. But not a range like 215-270MHz. A stepped range would be OK
if
there were enough steps. I don't mind (in fact it'd be quite useful) if
the
output was a divided form of the internal clock.
Don't care if it's linear or not, as long as it's stable enough that I can
draw a V/f graph.
The ability to keep the oscillator running but switch off the output pin.
No PLL.
It doesn't /have/ to be a VCO - if there's some other way to generate a
frequency on-chip that doesn't use a PLL that would be fine (ring
oscillators?).
Preferably plastic package.
It's only for experimental purposes so cost, board space etc isn't too
much
of an issue.
Don't care about supply voltage or logic levels
I'm quite happy to use some chip that uses an onboard oscillator for other
things internally, as long as I can turn on and off the clock on an output
pin.
This sounds like a nuts request, but I have a genuine reason for wanting
this :)
Something like the DS1085 looks perfect, except its top-end frequency is
much lower than I'd like. Any other suggestions?
Thanks
Theo
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